MCB 2610 Chapter Notes - Chapter 4: Archaea, Terpenoid, Isoprene
22 Sep 2016
School
Department
Course
Professor
Document Summary
By comparing ribosomal rna (rrna) nucleotide sequences we can determine the evolutionary relatedness of all living organisms. 16s or 18s rrna molecule is present in all known living organisms and fulfills basically the same biological function in all living organisms. Minor seq variations result from various mutations and will reflect the evolutionary distance between those two species. The 16s rrna seq shows that there archaeons are very distinct from bacteria and eukarya. Bacteria and archaea also lack membrane bound nucleus. Dna replication transcription and translation processes in archaeons seem to be eukarya- like. Archaeal dna is complexed with histones, dna binding proteins. Archaea and eukarya may have branched off from bacteria. Bacteria may be the closest relatives of the original life form. Many are rods or spheres, some spiral shaped, or irregular. Dna usually exists as a single circular molecule with no membrane surrounding (like bacteria) Some archaeons produce histones to help package dna into smaller condensed form.
